Method and apparatus for digesting wood and other fibrous materials.



v J. C. W. STANLEY. MBfgHoD AND APPARATUS FOR DIGBSTING Woon AND OTHERPIBRoUs MATERIALS. APPLICATION FILED JAN.6, 1911. RENEWED MAR. 28, 1913.

l,?5,?95 Patented 001;.1A1913.

Il IE '111/ lli''inlm ii A 'ing drawing, in which the mensions and builtof such ran srarns raar ortica,

JOHN CHARLES WILLIAM STANLEY, 0F SANTA CRUZ, CALIFORNIA, ASSIGNOR, BYDIRECT AND MESNE ASSIGNMENTS, TOXSTANLEY PAPER FIBRE COMPANY, 0E SAN'FRANCISCQ CALIFORNIA, A CORPORATION -OF ARIZONA.

METHOD AND APPARATUS FOR DIGESTING WOOD AND OTHER FIBROUS MATERIALS.

Specification of Letters Patent.

Patented Oct. 141, 1913.

Application led January, 1911, Serial No. 601,207. Renewed March 28,1913. Serial No. 757,482.

To-aZZ whom t may concern.'

Be it `known that l, JOHN CHARLES WIL- LIAM STANLEY, a subject of theKing ofl England, residing at Santa Grauz, in the county of Santa Cruzand State of California, have invented new and useful lmprovements inMethods and Apparatus for Digesting Vood and other Fibrous Materials, ofwhich the following is a specification.

This invention relates to a digester for the cooking of wood, straw,flax and other material for the manufacture vof pulp. Y The object ofthis invention is to provide a digester for cooking wood, straw, flaxand other fibrous material in large quantities; and to provide adigester involving details of construction designed to facilitate thefeedingY of the pulp into the digester; for efficiently and eifectuallydigesting the pulp and to facilitate its quick removal so as to producea substantially continuous digestion of material to be rendered intopulp.

The invention consists of the parts and the construction and combinationof parts, as hereinafter more fully described and claimed, havingreference to the accompany-V figure is a vertical sectional view of theimproved digester.

In the prese-nt embodiment of my invention I have shown the mainl bodyof the digester as comprising a vertically disposed cylinder which maybe of any suitable dimaterial as to be able to carry a pressure of from80 to 125 pounds, more or less, and which is provided y at its upper endwith a truncated coneshaped dome 2 and a similarly shaped bottom 3, eachof which members are provided with a steam tight door as 4 and 5.rThrough the upper one the material to be digested is charged into thedigester after the same has been previously filled with a suitablesolution of caustic soda, sulfate of soda, or other appropriatematerial. rlhe solution having been iirst heated in the digester toabout the boiling point by the application of steam or other heatedfluid which may be distributed through a vertical manifoldor pipe 6 fromwhich extend a plurality of branches 7 connected by any appropriatedevice to the body A of the dsuitable valve 16,

gester. Each of the several branches 7 is provided with a valve 8through which the admissionof fluid' from the pipe 6 may be admittedinto the digester A.

For the purpose of insuring a thorough subjection of the material to bedigested to the action of the solution in the digester there iscentrally mounted therein a Vertical, perforated tube 9 which isconnected by transverse or radially extending perforated pipes 10 to theconnections 7 with the main supply pipe 6 of which there may be oneprovided on each side of the digester. To

4the lower end of the perforated pipe 9 1s connected a drain pipe 12 inwhich is mounted a control valve 13 which may be opened at the properperiod to allow the fluid contents of the digester to drain therefrominto a condensing coil or other appropriate apparatus, as indicated at14.

There is connected to the dome 2 of the digester a. supply pipe 15adapted to convey air under pressure directly into the upper portionofthe body A, the flow of the fluid through the pipe 15 being controlledby a and from the pipe 15 is led a connection 17 joining with the mainsteam pipe 6 at its upper end. A valve 18- is provided in a pipe v19which joins with the steam pipe 6 to control the admission of steam tothe distributer 6.

The digester is opera-ted in the following manner: -Vlood or othermaterial to be treated, and which has been reduced to a predeterminedsize, is charged throughrthe top door 4 into the digester body A insufficient quantities to be practically submerged in the solutionpreviously 'supplied to the digester and which has been heated tol theboiling point by the admission of steam through the lower branches 7connected to the distributer 6, thus allowing the heated fluid to bedischarged .through the perforated pipes 9 and 10 into thezvolume of thesolution in the digester. During the pei riod when the heating mediumis`-being appliedl to the liquor in the digester those branches 7 whichare above the level of the solution or liquor are closed at their valves8 so that all the heating medium is directed into the lower portion ofthe digester, and at which time the valve 16 and the branch 17connecting the air pipe 15 with the digester 6 is closed. Thewoodorother material to be digested is gradually filled in in 16 openedsuilicient to allow a small quantity of compressed air to enter creatinga pressure in the upper part of the digester slightly in excess of thesteam pressure in the same which will result in the gradual Idischargeof t-he liquor in the perforating tube from which it` will drain fromthe digester through the condenser coil 14. The valve 13 is then closedagain and the digester filled with compressed air to a pressure of about100 pounds so as to thoroughly collect all of the fluid in the pulp inthe lower portion of the drain pipe 9 when the valve 13 may be againopened to permit the collected fluid to discharge through the coil 14,

and this collecting operation may be` repeat-ed yuntil the contents ofthe digester is sufiiciently cool to permit the discharge of the pulpthrough the bottom door 5.

In order to facilitate the discharge of the cooked pulp from thedigester and after the bottom door has been opened, air under suitablepressure may be admitted into the cone top 2, thus effectively forcingdownwardly the material in the digester and discharging it from thebottom openingat the door 5.

Having thus described my invention, what I claim and desire to secure byLetters Patent is- 1. The process' herein described for the digestion ofbrous material, said process consisting in immersing the material in adisintegrating solution; admitting a heating agent yinto the interior ofthe mass Vand subjecting the mass to the action of the heating agentuntil the mass is cooked; then draining 0H and-'condensing saidsolution; then admitting compressed air into thelcontainer above saidmass tofthereby create a ,pressureupon the mass in excess ing agent andto squeeze out of the mass the remaining surplus solution.

2. The process herein describedvfor the digestion pf fibrous material,said process consisting 1n immersing the materialin a disintegratingsolution; admitting a heating agent into the interior of the mass andsub- ]ecting the mass to the action of the heating agent unt-il the massis cooked; then vdraining ofi' and condensing said solution; then ofthat of the heat-` admission of compressed air above the mass l beingtreated.

4. rllhe f rocess herein described for the digestion o fibrous material,said process consisting in immersing thev material in a disintegratingsolution; admitting a heating agent into the interior of the mass andsubjecting the mass to the action of the heating agent until the mass iscooked; then draining off and condensing said solution; and finallyrapidly discharging the mass from the container by means-of air-pressureadmitted on top ofsaid mass.

5. In apparatus of the character described,

a container, a perforated vertical pipe centrally placed therein andother perforated pipes branching from the first pipe,means bywhich-steamv may be supplied .to said pipes and into the'body of themass being treated, and a condenser connecting with the lower part ofthe vertical pipe and into submerged is drained.

6. In apparatus of the character described a container, a perforatedvertical pipe cen# trally placed therein and other perforated pipesbranching from the first pipe, means by which steam may be supplied tosaid vpipes and into the body of the mass being which the solutionA inwhich'the mass isY treated, and a condenser connecting with the lowerpart of the vertical pipe and into which' the solution in which themass'is submerged is drained, and a compressed air pipe leading into theupper part of the container.

7. In apparatus of the character described,

1 15 perforated pipes branching from the first pipe, meansl a container,a perforated vertical pipe centrally placed therein and other by whichsteam' may be supplied to said pipes and into the body of the mass beingtreated, and a condenser connecting withthe lower part of thev vertical.pipe and into which the solution in which the mass is submerged isdrained, said container having a.

bottom discharge, .and a pipe-leading compressed air into the upper partof the container and adapted to exert a pressure on the mass of materialto rapidly deliver the same through said bottom discharge.

8. The processI which consists in cooking the material to of digestingwood pulp be digested in a closed vessel in the presence In testimonywhereof have hereunto set of a suitable disintegrating solution by permyhand in the presence of two subscribing 1o colating steam through themass, then turn- Witnesses. ing 0E the steam and discharging the liquorfrom the vessel by Huid pressure, then e001- JOHN CHARLES WILLIAMSTANLEY' ing the Wood puip so drained inthe vessel Witnesses:

by compressed alr, and finally discharging UDEN E. SMITH,

the cooled pulp. J. F. GALLAGHER.

